A method for controlling a stepless transmission used in a motor vehicle is known from German Patent Publication DE 41 06 471 A1. The transmission is thereby constructed as a looping transmission with two bevel disc gears and a looping belt, whereby the bevel disc wheels are coupled to one another through the looping belt. Each bevel gear disc comprises an axially displaceable bevel disk functioning as an adjustment means. The transmission ratio of the transmission can be adjusted in a stepless manner by a shifting of the adjustment means within a range that is limited by two transmission ratio end values. Hereby it is disadvantageous that a transmission ratio end values are depending on manufacturing tolerances and on wear and tear phenomena. Additionally, the transmission ratio end values can vary dynamically depending on the slip between the bevel disc gears and the looping belt so that the adjustment means are moved into end positions that are determined by mechanical displacement stop when the transmission is operating with a maximal or minimal transmission ratio. High end position forces are effective on the adjustment means in the end positions which have an adverse influence on the efficiency and the useful life of the transmission.
It is known from European Patent Publication EP 785,381 A1 that the running of the adjustment means into their mechanical end position is undesirable. Such an undesirable operation can be avoided in that a safety clearance to the transmission ratio end values is maintained, which, however has proven itself to be disadvantageous because an optimal operation with a maximum or minimum permissible transmission ratio is not possible for certain driving strategies.